In “What Went Wrong,” best-selling author Jerome Corsi reveals how some major voices in mainstream Christianity went out of their way to make sure the voting public was aware of Romney’s beliefs.

Corsi notes that in October 2011, just 13 months before Election Day, Robert Jeffress, pastor of First Baptist Church in Dallas, Texas, caused a commotion at the Values Voter Summit when he warned against voting for Romney because “Mormonism is not Christianity,” claiming the decision for evangelical Christians is whether “we prefer someone who is truly a believer in Jesus Christ or someone … who is part of a cult.”

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Even non-Christians piled on.

The book notes that after the outburst by Jeffress, the next shot came from world-famous atheist Christopher Hitchens.

"The Mormons apparently believe that Jesus will return in Missouri rather than Armageddon: I wouldn't care to bet on the likelihood of either," Hitchens wrote in an October 17, 2011, article in Slate magazine that examined what he characterized as Romney's Mormon problem.

"In the meanwhile, though, we are fully entitled to ask Mitt Romney about the forces that influenced his political formation and – since he comes from a dynasty of his church, and spent much of his boyhood and manhood first as a missionary and then as a senior lay official – it is safe to assume that the influence is not small."

Craig L. Foster, who is Mormon and a historian of the faith, studied the 2008 election cycle and claimed there was obvious press bias when the Associated Press published an article in February 2007 titled "Romney family tree has polygamy branch."

In contrast, Corsi explains, "the mainstream media neglected to mention the polygamy at the heart of Barack Obama's life story, in that Obama's father, the Kenyan Barack Obama, had multiple wives and was married to a woman in Africa at the same time he married Ann Dunham and conceived the future president."

One year before the election, the Pew Forum on Religion and Public Life published a survey on Romney's Mormon faith, concluding it would be a factor in the GOP primaries, but not in the general election.

The Pew Research Center found that about half of all voters and 60 percent of evangelical Republicans knew that Mitt Romney was a Mormon.

The study also found evangelical Protestants, a key element of the GOP electoral base, are more inclined than the public as a whole to view Mormonism as a non-Christian faith.

Republicans who replied Mormonism was not a Christian religion were found to be less likely to support Romney for the GOP nomination, but these same Republicans were prepared to back Romney overwhelmingly in a run against Barack Obama in the general election.

When asked if the 2012 election were a choice between Mitt Romney and Barack Obama, 87 percent the GOP respondents said they would support Romney, compared to only 9 percent who would support Obama.

"There is no evidence that Romney's Mormon faith would prevent rank-and-file Republicans, including white evangelicals, from coalescing around him if he wins the GOP nomination," the executive summary of the Pew report read. "Rather, the same Republicans who may have doubts about Romney's faith are among the most vehement opponents of Barack Obama. Fully 91% of white evangelical Republican voters say they would back Romney over Obama in a general election matchup, and 79% would support Romney strongly. Overall, white evangelicals would be among the strongest Romney supporters if he is the GOP nominee challenging Obama next fall."

As for how Romney himself handled the issue, Corsi explain the strategy was one of silence, treating the issue of Mormonism as a nonissue.

"Immediately after Pastor Jeffress forced the topic of Romney's faith onto the headlines in October 2011," Corsi writes, "reporters trailing Romney in New Hampshire began peppering him with questions. CNN reported that Romney kept silent, shaking hands with crowds in the granite state, while aides shouted, 'No questions,' in an effort to quiet the press."

CNN reported the news media's persistence on the issue irritated the Republican candidate.

"I do press avails and then I answer questions that are important questions in the length that I want to do but what I don't do is in a group like this is [sic] stop and rattle off questions to people just as we walk along," Romney shot back to the press.

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In October 2012, about a year after Pastor Jeffress said Romney was in a cult, legendary evangelist Billy Graham, then 93, met with Romney in his North Carolina home.

"It was an honor to meet and host Gov. Romney in my home today, especially since I knew his late father, former Michigan Gov. George Romney, whom I considered a friend," Graham said. "I have followed Mitt Romney's career in business, the Olympic Games, as governor of Massachusetts and, of course, as a candidate for president of the United States."

Graham praised Romney's character: "What impresses me even more than Gov. Romney's successful career are his values and strong moral convictions. I appreciate his faithful commitment to his impressive family, particularly his wife Ann of 43 years and his five married sons."

Graham even stressed he prayed with Romney: "It was a privilege to pray with Gov. Romney – for his family and our country. I will turn 94 the day after the upcoming election, and I believe America is at a crossroads. I hope millions of Americans will join me in praying for our nation and to vote for candidates who will support the biblical definition of marriage, protect the sanctity of life and defend our religious freedoms."

According to exit polls, Romney's faith did not hurt him in the 2012 race.

The Washington Post reported the day after the election that 78 percent of white evangelical Christians went for Romney, up from 74 percent for John McCain in 2008. Moreover, evangelical Christians turned out to vote equally for Romney and McCain, with the Post reporting that white evangelical Christians were 26 percent of the electorate in both 2008 and 2012.

Corsi noted Kathryn Lofton, a professor of religious studies at Yale University, argued persuasively that Romney lost not because he was a Mormon, but because he was not Mormon enough.

"She says that successful presidential candidates explain to the electorate how the strangest parts of themselves make sense," Corsi writes. "She praised Obama for transforming his 'itinerant childhood and complicated genealogy' into a story average Americans could understand and relate to. Romney's mistake, she contends, was his failure to unveil the relationship between his particular religious experience and his vision of America."

Lofton explained:

"He should have announced at every pit stop that he had met the world through his missionary work; that he came from a good Christian home that emphasized the principles of hard work and self-sacrifice; that he keeps a weekly calendar guided by the principles of Stephen R. Covey; and keeps a marriage because he believes those commercials are right – diamonds are forever, and so is this bond. He should have proclaimed his financial success was the result of all this earnestness, and explained private equity as just another way to organize free enterprise. Not because it's a crafty re-framing of his biography, but because it is also true: it's true to the very thing his supporters find so solid, and his detractors find so discomfiting, about Romney."